The present invention generally relates to a method and a system for determining manufacturing throughput targets for each product type produced at a manufacturing facility that employs a work-in-progress (WIP) management system.
Many industrial products require multiple sequential processing steps during manufacturing. The quantity of manufactured industrial products in a production facility can be maximized by any one of many different production management systems depending on the nature of the products, the variety of the products, and the complexity of the processes employed during individual manufacturing steps, and the distribution and uniformity of processing time for each manufacturing step.
A production management system commonly employed to manufacture products that require a large number of processing steps is called a work-in-progress (WIP) management system. Examples of prior art WIP management systems include those described in U.S. Pat. Nos. 5,826,238 to Chen et al. and 7,239,930 to Burda et al. K. Miyashita et al. “Simulation-based advanced WIP management and control in semiconductor manufacturing,” Proc. 2004 Winter Simulation Conf., pp. 1943-1950 (2004), W. Hopp et al., “Setting WIP levels with statistical throughput control (STC) in CONWIP production lines,” Int. J. Prod. Res., vol. 36, No. 4, pp. 867-882 (1998), H. Hu et al., “A dynamic WIP control strategy for bottlenecks in a wafer fabrication system,” Int. J. Prod. Res. 2009, pp. 1-13 (2009).
Despite the availability of diverse methods for managing WIP in a production control system, processing data on current WIP distribution to derive a coherent WIP management plan that can handle a large number of product types and equitably balance the final output of these product types at production facilities has remained a difficult task when such methods have been applied in practice.